/* * Copyright (C) 2003 Bernardo Innocenti * * Based on former do_div() implementation from asm-parisc/div64.h: * Copyright (C) 1999 Hewlett-Packard Co * Copyright (C) 1999 David Mosberger-Tang * * * Generic C version of 64bit/32bit division and modulo, with * 64bit result and 32bit remainder. * * The fast case for (n>>32 == 0) is handled inline by do_div(). * * Code generated for this function might be very inefficient * for some CPUs. __div64_32() can be overridden by linking arch-specific * assembly versions such as arch/ppc/lib/div64.S and arch/sh/lib/div64.S * or by defining a preprocessor macro in arch/include/asm/div64.h. */ #include #include #include /* Not needed on 64bit architectures */ #if BITS_PER_LONG == 32 #ifndef __div64_32 uint32_t __attribute__((weak)) __div64_32(uint64_t *n, uint32_t base) { uint64_t rem = *n; uint64_t b = base; uint64_t res, d = 1; uint32_t high = rem >> 32; /* Reduce the thing a bit first */ res = 0; if (high >= base) { high /= base; res = (uint64_t) high << 32; rem -= (uint64_t) (high*base) << 32; } while ((int64_t)b > 0 && b < rem) { b = b+b; d = d+d; } do { if (rem >= b) { rem -= b; res += d; } b >>= 1; d >>= 1; } while (d); *n = res; return rem; } EXPORT_SYMBOL(__div64_32); #endif #ifndef div_s64_rem s64 div_s64_rem(s64 dividend, s32 divisor, s32 *remainder) { u64 quotient; if (dividend < 0) { quotient = div_u64_rem(-dividend, abs(divisor), (u32 *)remainder); *remainder = -*remainder; if (divisor > 0) quotient = -quotient; } else { quotient = div_u64_rem(dividend, abs(divisor), (u32 *)remainder); if (divisor < 0) quotient = -quotient; } return quotient; } EXPORT_SYMBOL(div_s64_rem); #endif /** * div64_u64_rem - unsigned 64bit divide with 64bit divisor and remainder * @dividend: 64bit dividend * @divisor: 64bit divisor * @remainder: 64bit remainder * * This implementation is a comparable to algorithm used by div64_u64. * But this operation, which includes math for calculating the remainder, * is kept distinct to avoid slowing down the div64_u64 operation on 32bit * systems. */ #ifndef div64_u64_rem u64 div64_u64_rem(u64 dividend, u64 divisor, u64 *remainder) { u32 high = divisor >> 32; u64 quot; if (high == 0) { u32 rem32; quot = div_u64_rem(dividend, divisor, &rem32); *remainder = rem32; } else { int n = 1 + fls(high); quot = div_u64(dividend >> n, divisor >> n); if (quot != 0) quot--; *remainder = dividend - quot * divisor; if (*remainder >= divisor) { quot++; *remainder -= divisor; } } return quot; } EXPORT_SYMBOL(div64_u64_rem); #endif /** * div64_u64 - unsigned 64bit divide with 64bit divisor * @dividend: 64bit dividend * @divisor: 64bit divisor * * This implementation is a modified version of the algorithm proposed * by the book 'Hacker's Delight'. The original source and full proof * can be found here and is available for use without restriction. * * 'http://www.hackersdelight.org/hdcodetxt/divDouble.c.txt' */ #ifndef div64_u64 u64 div64_u64(u64 dividend, u64 divisor) { u32 high = divisor >> 32; u64 quot; if (high == 0) { quot = div_u64(dividend, divisor); } else { int n = 1 + fls(high); quot = div_u64(dividend >> n, divisor >> n); if (quot != 0) quot--; if ((dividend - quot * divisor) >= divisor) quot++; } return quot; } EXPORT_SYMBOL(div64_u64); #endif /** * div64_s64 - signed 64bit divide with 64bit divisor * @dividend: 64bit dividend * @divisor: 64bit divisor */ #ifndef div64_s64 s64 div64_s64(s64 dividend, s64 divisor) { s64 quot, t; quot = div64_u64(abs(dividend), abs(divisor)); t = (dividend ^ divisor) >> 63; return (quot ^ t) - t; } EXPORT_SYMBOL(div64_s64); #endif #endif /* BITS_PER_LONG == 32 */ /* * Iterative div/mod for use when dividend is not expected to be much * bigger than divisor. */ u32 iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder) { return __iter_div_u64_rem(dividend, divisor, remainder); } EXPORT_SYMBOL(iter_div_u64_rem); l'>space:mode:
authorGabriel Krisman Bertazi <krisman@collabora.co.uk>2017-01-16 12:23:42 -0200
committerUlf Hansson <ulf.hansson@linaro.org>2017-01-31 11:26:49 +0100
commit161e6d44a5e2d3f85365cb717d60e363171b39e6 (patch)
tree5c8b730a137696ef979f05ceae869b6e0348794c /drivers/usb/storage/realtek_cr.c
parent566cf877a1fcb6d6dc0126b076aad062054c2637 (diff)
mmc: sdhci: Ignore unexpected CARD_INT interrupts
One of our kernelCI boxes hanged at boot because a faulty eSDHC device was triggering spurious CARD_INT interrupts for SD cards, causing CMD52 reads, which are not allowed for SD devices. This adds a sanity check to the interruption path, preventing that illegal command from getting sent if the CARD_INT interruption should be disabled. This quirk allows that particular machine to resume boot despite the faulty hardware, instead of getting hung dealing with thousands of mishandled interrupts. Suggested-by: Adrian Hunter <adrian.hunter@intel.com> Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.co.uk> Acked-by: Adrian Hunter <adrian.hunter@intel.com> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Cc: <stable@vger.kernel.org>
Diffstat (limited to 'drivers/usb/storage/realtek_cr.c')